/* 
 * Copyright 2006-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.anyline.util;

import java.awt.image.BufferedImage;  
import java.io.File;  
import java.io.FileInputStream;  
import java.io.FileNotFoundException;  
import java.io.IOException;  
import java.io.InputStream;  
import java.util.HashMap;  
import java.util.Iterator;  
import java.util.Map;  
import java.util.Map.Entry;  
import javax.imageio.ImageIO;  
import javax.imageio.ImageReader;  
import javax.imageio.stream.ImageInputStream;  
    
public class FileTypeUtil{    
    public final static Map<String, String> FILE_TYPE_MAP = new HashMap<String, String>();    
        
    private FileTypeUtil(){}    
    static{    
        getAllFileType();  //初始化文件类型信息    
    }    
    private static void getAllFileType(){
        FILE_TYPE_MAP.put("jpg", "FFD8FF"); 						//JPEG (jpg)    
        FILE_TYPE_MAP.put("png", "89504E47");  						//PNG (png)    
        FILE_TYPE_MAP.put("gif", "47494638");  						//GIF (gif)    
        FILE_TYPE_MAP.put("tif", "49492A00");  						//TIFF (tif)    
        FILE_TYPE_MAP.put("bmp", "424D"); 							//Windows Bitmap (bmp)    
        FILE_TYPE_MAP.put("dwg", "41433130");			 			//CAD (dwg)    
        FILE_TYPE_MAP.put("html", "68746D6C3E");  					//HTML (html)    
        FILE_TYPE_MAP.put("rtf", "7B5C727466");  					//Rich Text Format (rtf)    
        FILE_TYPE_MAP.put("xml", "3C3F786D6C");    
        FILE_TYPE_MAP.put("zip", "504B0304");    
        FILE_TYPE_MAP.put("rar", "52617221");    
        FILE_TYPE_MAP.put("psd", "38425053");  						//Photoshop (psd)    
        FILE_TYPE_MAP.put("eml", "44656C69766572792D646174653A");  	//Email [thorough only] (eml)    
        FILE_TYPE_MAP.put("dbx", "CFAD12FEC5FD746F");  				//Outlook Express (dbx)    
        FILE_TYPE_MAP.put("pst", "2142444E");  						//Outlook (pst)    
        FILE_TYPE_MAP.put("xls", "D0CF11E0");  						//MS Word    
        FILE_TYPE_MAP.put("doc", "D0CF11E0");  						//MS Excel 注意：word 和 excel的文件头一样    
        FILE_TYPE_MAP.put("mdb", "5374616E64617264204A");  			//MS Access (mdb)    
        FILE_TYPE_MAP.put("wpd", "FF575043"); 						//WordPerfect (wpd)     
        FILE_TYPE_MAP.put("eps", "252150532D41646F6265");    
        FILE_TYPE_MAP.put("ps", "252150532D41646F6265");    
        FILE_TYPE_MAP.put("pdf", "255044462D312E");  				//Adobe Acrobat (pdf)    
        FILE_TYPE_MAP.put("qdf", "AC9EBD8F");  						//Quicken (qdf)    
        FILE_TYPE_MAP.put("pwl", "E3828596");  						//Windows Password (pwl)    
        FILE_TYPE_MAP.put("wav", "57415645"); 						//Wave (wav)    
        FILE_TYPE_MAP.put("avi", "41564920");    
        FILE_TYPE_MAP.put("ram", "2E7261FD");  						//Real Audio (ram)    
        FILE_TYPE_MAP.put("rm", "2E524D46");  						//Real Media (rm)    
        FILE_TYPE_MAP.put("mpg", "000001BA");  						//    
        FILE_TYPE_MAP.put("mov", "6D6F6F76");  						//Quicktime (mov)    
        FILE_TYPE_MAP.put("asf", "3026B2758E66CF11"); 				//Windows Media (asf)    
        FILE_TYPE_MAP.put("mid", "4D546864");  						//MIDI (mid)    
    }    
    
    
    /**  
     * Created on 2010-7-1   
     * <p>Discription:[getImageFileType,获取图片文件实际类型,若不是图片则返回null]</p>  
     * @param File  
     * @return fileType  
     */    
    public final static String getImageFileType(File f)    
    {    
        if (isImage(f))  
        {  
            try  
            {  
                ImageInputStream iis = ImageIO.createImageInputStream(f);  
                Iterator<ImageReader> iter = ImageIO.getImageReaders(iis);  
                if (!iter.hasNext())  
                {  
                    return null;  
                }  
                ImageReader reader = iter.next();  
                iis.close();  
                return reader.getFormatName();  
            }  
            catch (IOException e)  
            {  
                return null;  
            }  
            catch (Exception e)  
            {  
                return null;  
            }  
        }  
        return null;  
    }    
    
    /**  
     * Created on 2010-7-1   
     * <p>Discription:[getFileByFile,获取文件类型,包括图片,若格式不是已配置的,则返回null]</p>  
     * @param file  
     * @return fileType  
     */    
    public final static String getFileByFile(File file)    
    {    
        String filetype = null;    
        byte[] b = new byte[50];    
        try    
        {    
            InputStream is = new FileInputStream(file);    
            is.read(b);    
            filetype = getFileTypeByStream(b);    
            is.close();    
        }    
        catch (FileNotFoundException e)    
        {    
            e.printStackTrace();    
        }    
        catch (IOException e)    
        {    
            e.printStackTrace();    
        }    
        return filetype;    
    }    
        
    /**  
     * Created on 2010-7-1   
     * <p>Discription:[getFileTypeByStream]</p>  
     * @param b  
     * @return fileType  
     */    
    public final static String getFileTypeByStream(byte[] b)    
    {    
        String filetypeHex = String.valueOf(getFileHexString(b));    
        Iterator<Entry<String, String>> entryiterator = FILE_TYPE_MAP.entrySet().iterator();    
        while (entryiterator.hasNext()) {    
            Entry<String,String> entry =  entryiterator.next();    
            String fileTypeHexValue = entry.getValue();    
            if (filetypeHex.toUpperCase().startsWith(fileTypeHexValue)) {    
                return entry.getKey();    
            }    
        }    
        return null;    
    }    
        
    /** 
     * Created on 2010-7-2  
     * <p>Discription:[isImage,判断文件是否为图片]</p> 
     * @param file 
     * @return true 是 | false 否 
     */  
    public static final boolean isImage(File file){  
        boolean flag = false;  
        try  
        {  
            BufferedImage bufreader = ImageIO.read(file);  
            int width = bufreader.getWidth();  
            int height = bufreader.getHeight();  
            if(width==0 || height==0){  
                flag = false;  
            }else {  
                flag = true;  
            }  
        }  
        catch (IOException e)  
        {  
            flag = false;  
        }catch (Exception e) {  
            flag = false;  
        }  
        return flag;  
    }  
      
    /**  
     * Created on 2010-7-1   
     * <p>Discription:[getFileHexString]</p>  
     * @param b  
     * @return fileTypeHex  
     */    
    public final static String getFileHexString(byte[] b)    
    {    
        StringBuilder stringBuilder = new StringBuilder();    
        if (b == null || b.length <= 0)    
        {    
            return null;    
        }    
        for (int i = 0; i < b.length; i++)    
        {    
            int v = b[i] & 0xFF;    
            String hv = Integer.toHexString(v);    
            if (hv.length() < 2)    
            {    
                stringBuilder.append(0);    
            }    
            stringBuilder.append(hv);    
        }    
        return stringBuilder.toString();    
    }   

    public static void main(String[] args) throws Exception    
    {    
        File f = new File("d://YeePaySecureGuard.msi");    
        if (f.exists())    
        {    
            String filetype1 = getImageFileType(f);    
            System.out.println(filetype1);    
            String filetype2 = getFileByFile(f);    
            System.out.println(filetype2);    
        }    
    }    
} 
